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3.10 Geology, Soils, Seismicity, and Paleontological 

Resources

3.10.1 Introduction

This section identifies the existing geology, soils, and seismic conditions, including paleontological 

and mineral resources within the Tier 1/Program EIS/EIR Study Area and provides an evaluation of 

the No Build Alternative and the Build Alternative Options in relation to existing geological, mineral,

and paleontological conditions. 

3.10.2 Regulatory Framework

In accordance NEPA (42 USC Section 4321 et seq.), CEQ regulations implementing NEPA (40 CFR 

Parts 1501-1508), FRA’s Procedures for Considering Environmental Impacts (64 FR 28545, May 

26, 1999) and CEQA, FRA identified the prevailing geological and paleontological conditions within 

the Tier 1/Program EIS/EIR Study Area and evaluated the potential impacts on geology, soils, 

mineral resources, and paleontological resources as a result of implementing the Build Alternative 

Options. 

Federal

Earthquake Hazards Reduction Act

In October 1977, the U.S. Congress passed the Earthquake Hazards Reduction Act to reduce the 

risks to life and property from future earthquakes in the U.S. through the establishment and 

maintenance of an effective earthquake hazards reduction program. To accomplish this goal, the 

Earthquake Hazards Reduction Act established the National Earthquake Hazards Reduction 

Program, which was further refined by the National Earthquake Hazards Reduction Program Act.

Track Safety Standards 

Section 213.239, Special Inspections, of 49 CFR Part 213 requires that, in the event of fire, flood, 

severe storm, or other occurrence that might have damaged track structure, a special inspection 

shall be made of the track involved as soon as possible after the occurrence and, if possible, before 

the operation of any train over that track.
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Paleontological Resources Preservation Act

The proposed rule (43 CFR Part 49, Paleontological Resources Preservation, November 21, 2016) 

would implement the Paleontological Resources Preservation Act of 2009 by providing standards for 

a coordinated approach to the management of paleontological resources on public lands. The rule 

clarifies how bureaus will manage paleontological resources to ensure they are available for current 

and future generations to enjoy as part of America’s national heritage.

Uniform Building Code 

The Uniform Building Code (UBC) is published by the International Conference of Building Officials 

and forms the basis for California’s building code, as well as approximately half of the state building 

codes in the U.S. It has been adopted by the California Legislature to address the specific building 

conditions and structural requirements for California, as well as provide guidance on foundation 

design and structural engineering for different soil types.

State

Alquist-Priolo Earthquake Fault Zoning Act

The Alquist-Priolo (AP) Earthquake Fault Zoning Act (California PRC Sections 2621–2630) was 

passed into law following the destructive February 9, 1971 San Fernando earthquake, which was 

associated with extensive surface fault ruptures that damaged numerous structures. The act 

provides a mechanism for reducing losses from surface fault rupture on a statewide basis. The intent 

of the act is to ensure public safety by prohibiting the siting of most structures for human occupancy 

across traces of active faults that constitute a potential hazard to structures from surface faulting or 

fault creep.

California Building Code

California provides minimum standards for building design through the (Title 24). The 2016 California 

Building Code became effective January 1, 2017. With the shift from seismic zones to seismic 

design, the California Building Code philosophy has shifted from life safety design to collapse 

prevention, meaning that structures are designed for prevention of collapse for the maximum level of 

ground shaking that could reasonably be expected to occur at a site.
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California Surface Mining and Reclamation Act of 1975

The CGS, formerly the California Division of Mines and Geology, classifies the regional significance 

of mineral resources in accordance with the Surface Mining and Reclamation Act of 1975 (California 

PRC Sections 2710-2796) and assists CGS in the designation of lands containing significant 

aggregate resources. Surface Mining and Reclamation Act regulates surface mining operations to 

ensure that adverse environmental impacts are minimized, and mined lands are reclaimed to a 

usable condition. Surface Mining and Reclamation Act also encourages the production, 

conservation, and protection of California’s mineral resources.

California Public Resource Code

The California PRC includes provisions for the handling of paleontological resources. Specifically, 

PRC 5097.5 provides for the protection of paleontological resources and prohibits the removal, 

destruction, injury, or defacement of paleontological features on any lands under the jurisdiction of 

state or local authorities. PRC 30244 requires reasonable mitigation for impacts on paleontological 

resources that occur as a result of development.

Seismic Hazards Mapping Act

The California Department of Conservation provides guidance to the Seismic Hazards Mapping Act, 

which aims to reduce the threat of seismic hazard to public health and safety by identifying and 

mitigating seismic hazards. State, county, and city agencies are directed to utilize such maps in land 

use and permitting processes. The act also requires geotechnical investigations specific to the site 

be conducted before permitting occurs on sites within seismic hazard zones.

Regional

Goals and policies related to geology, soils, seismicity, paleontological, and mineral resources

applicable to the Program were identified in the Los Angeles, Orange, San Bernardino, and 

Riverside Counties’ general plans.

Los Angeles County 2035 General Plan

The Safety Element of the Los Angeles County 2035 General Plan (County of Los Angeles 2015) 

provides goals, objectives, policies, and programs related to hazards mitigation, emergency 

response, fire hazards, seismic/geotechnical hazards, and disaster recovery. The Safety Element

identifies policies to reduce the potential risk of death, injuries, and economic damage resulting from 

natural and man-made hazards. The general plan prohibits new projects, as defined by the AP Act 

and Seismic Hazards Mapping Acts, until a comprehensive geotechnical study has been completed.
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The Conservation and Natural Resources Element of the Los Angeles County 2035 General Plan

provides goals, objectives, policies, and programs related to conservation of paleontological and 

mineral resources. Mineral resource policies include the protection of mineral resource zones (MRZ)

from development and incompatible adjacent land uses and the management of identified mineral 

resources that allows for access, development, and conservation of mineral resources. 

Paleontological resource policies include the proper notification, mitigation, and recovery process for 

development on or near paleontological resources.

Orange County General Plan

The Safety Element of the Orange County General Plan (Orange County 2005) provides goals, 

objectives, and policies related to hazards that primarily impact persons and property in the 

unincorporated areas of Orange County and includes information on seismic and geologic hazards,

including landslides, land subsidence, erosion, and soil characteristics.

The Resources Element of the Orange County General Plan provides goals, objectives, policies, and 

programs related to conservation of paleontological and mineral resources. Mineral resource policies 

include the protection of all mineral lands consistent with sound resource management practices and 

to reduce dependence on imported mineral resources for existing and future needs. Paleontological 

resource policies include identifying paleontological resource through literature, records research, 

and surface surveys and the proper notification, mitigation, and recovery process for paleontological 

resources for cultural, scientific, and education needs.

County of Riverside General Plan

The Safety Element of the County of Riverside General Plan (County of Riverside 2003) serves as 

the framework by which safety considerations are introduced into the land use planning process and 

identifies existing hazards and policies to reduce hazards for development. 

The Open Space Element of the County of Riverside General Plan provides goals, objectives, 

policies, and programs related to conservation of paleontological and mineral resources. Mineral 

resource policies include the restriction of incompatible land uses within areas of existing or potential 

surface mining areas. The Open Space Element of the County of Riverside General Plan recognizes 

the importance of paleontological resources with the development of policies to ensure these 

resources are considered in project planning. These policies include the preparation of 

paleontological resource impact mitigation program and the proper documentation, curation, and 

mitigation of impacts on paleontological resources. 
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County of San Bernardino General Plan

The Safety Element of the County of San Bernardino General Plan (County of San Bernardino 2014)

provides information on geologic hazards, seismic activity, landslides and mudslides, ground 

subsidence, volcanic activity, and wind/erosion and identifies goals and policies to reduce the 

potential risk of death, injuries, property damage, and economic and social dislocation resulting from 

fires, floods, earthquakes, landslides, and other hazards.

The Natural Resources Element of the County of San Bernardino General Plan provides goals, 

objectives, policies, and programs related to conservation of paleontological and mineral resources. 

Mineral resource policies include the prioritization of MRZ-2 lands by prohibiting or discouraging 

development of land that would preclude future development of mining facilities. Paleontological 

resource policies include the avoidance of paleontological resources whenever feasible and salvage 

and preservation of resources if avoidance is not possible. 

Local and Tribal Governments

Regulations from cities, local agencies, and tribal governments would be identified in the Tier 

2/Project-level analysis once site-specific rail infrastructure improvements and station locations are 

known. 

3.10.3 Methods for Evaluating Environmental Effects

The methodology for the geological and paleontological evaluation consists of a service-level 

qualitative, and—where possible—quantitative, analysis that compares relative effects on geology, 

soils, mineral resources, and paleontological resources as a result of implementing each of the Build 

Alternative Options. A detailed evaluation that will identify Project-specific geotechnical engineering 

and permitting requirements will be completed for the Tier 2/Project-level analysis.

Geologic resources include subsurface geologic conditions and soil resources that can provide value 

or are useful to society. Geologic hazards associated with these and other geologic resources could 

pose potential danger to the built and natural environment. Geologic hazards include soils with steep 

slopes and high landslide susceptibility and seismic conditions.

The geologic setting is described in terms of the underlying geologic conditions and soil type. Due to 

the regional nature of the physical geological environment, seismic hazards (faults, ground shaking, 

liquefaction, and slope stability) in the Tier 1/Program EIS/EIR Study Area, as defined below, are

described on a countywide basis. The likelihood for expansive soils, corrosive soils, and soil erosion 

is also described. Data, based on available GIS data, is tabulated by county.
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To assess potential effects related to geology, soils, and mineral resources, aerial mapping was

used to obtain information for the Tier 1/Program EIS/EIR Study Area. Active faults, MRZs, ground 

shaking, liquefaction, slope stability, and soil type were evaluated in the analysis.

Paleontological research for the Tier 1/Program EIS/EIR includes a geologic map review, 

paleontological sensitivity map review, soil typology review, and search of readily available literature 

for the Eastern Section under the Build Alternative Options. The results of the research were used to 

complete a paleontological sensitivity analysis, along with a qualitative assessment of potential 

effects on paleontological resources from implementation of the Eastern Section under Build 

Alternative Options 1, 2, and 3. The Western Section utilizes existing rail infrastructure, and no 

additional track improvements would be required to accommodate the proposed service; therefore, 

no ground disturbance would occur with implementation of the Build Alternative Options. As such, 

record searches and archival research were only conducted for the Eastern Section because ground 

disturbance would be required for the infrastructure improvements proposed for this section.

Tier 1/Program EIS/EIR Study Area

This service-level evaluation is limited to a desktop analysis of the data sources described in 

Section 3.10.3. The Tier 1/Program EIS/EIR Study Area was combined with GIS overlays to identify 

areas where seismic and geologic hazards may occur (e.g., ground shaking, liquefaction, slope 

stability and the likelihood for expansive soils, corrosive soils, and soil erosion) and where potential 

environmental resources (e.g., paleontological or mineral resources) could be affected by the 

Program. These potential areas were identified on a broad scale using available mapping 

information. A detailed description of the Tier 1/Program EIS/EIR Study Area is provided in Section 

3.1, Introduction to Environmental Analysis, of this Tier 1/Program EIS/EIR. 

Data Sources

Online GIS data sources available from USGS, CGS, and a variety of other sources were used to 

identify areas containing potential seismic/geologic hazards, paleontological resources, and mineral 

resources within the Tier 1/Program EIS/EIR Study Area. Specifically, the following resources were 

reviewed:

• Earthquake Hazards Program: Stores information reported by USGS on identified active 

faults and landslide susceptibility, data on the dates of seismic activity for active faults, and 

maps of soils that have physical properties or topographic position susceptible to landslides
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• Earthquakes and Faults Program: Stores information reported by CGS related to ground 

motion earthquake records, distribution of historic earthquakes, and maps showing potential 

for ground shaking, fault rupture, liquefaction, and seismically induced landslides in 

California.

• Mineral Resource Mapping: Stores information generated by CGS that identify mineral 

resources zones with the potential for production of geologic resources, such as metals, 

minerals, and construction aggregate important to the state’s economy

• Mines Online Interactive Map: A California Department of Conservation (Division of Mine 

Reclamation) database that provides information such as mine name, mine status, 

commodity sold, location, and other mine-specific data

Related Resources

There are no related resources that would contribute to the assessment of Tier 1/Program EIS/EIR 

effects on geology, soils, mineral resources, and paleontological resources.

3.10.4 Affected Environment

Southern California straddles the Pacific tectonic plate and the North American tectonic plate. The 

slow movements of these plates over time has created a complex and diverse geological setting 

unique to this region. Evidence of historic seismic activity is present in the numerous mountain 

ranges, valleys, canyons, and other geological features in the region. Present seismic activity is 

apparent in the numerous faults throughout the region, earthquakes, liquefaction, and landslides.

The Program Corridor is approximately 144 miles long and traverses a diverse geological area from 

its western terminus in the Los Angeles Basin to its eastern terminus in the Coachella Valley. The 

majority of the Program Corridor from the Los Angeles Basin to San Gorgonio Pass is located at the 

boundary of the Transverse Ranges Geomorphic Province and the northern Peninsular Ranges 

Geomorphic Province. The topography crossed by the Program Corridor ranges from relatively flat, 

urban landscapes in the Western Section to hilly canyons in the central portion, and flat, low desert 

habitat in the Eastern Section. Elevations within the Program Corridor range from 300 feet above 

mean sea level at the western terminus in Los Angeles up to 600 feet in Corona, 1,000 feet in 

Colton, and 2,600 feet in Beaumont (highest elevation), and down to 75 feet below mean sea level at 

the eastern terminus in Coachella (lowest elevation). From San Gorgonio Pass to the Coachella

Valley, the Tier 1/Program EIS/EIR Study Area lies at the boundary of the Peninsular Ranges 

Geomorphic Province and the Colorado Desert Geomorphic Province. 
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The majority of the Tier 1/Program EIS/EIR Study Area is underlain by marine and non-marine 

sedimentary rock of the Holocene Age and Pleistocene Age consisting of unconsolidated and semi 

consolidated alluvium, lake, playa, and terrace deposits.

Earthquake Faults and Alquist-Priolo Fault Zones 

The Tier 1/Program EIS/EIR Study Area is located within an active seismic region and is expected to 

experience ground shaking from an earthquake occurring along several major active or potentially 

active faults in Southern California. The probability that the Tier 1/Program EIS/EIR Study Area 

would be subject to strong seismic shaking is considered moderate to high, due to the proximity of 

known active faults in the region. The USGS 1-year probabilistic seismic hazard forecast for induced 

and natural earthquakes indicates that Los Angeles County, Orange County, southwest San 

Bernardino County, and the western half of Riverside County have a 2 to 5 percent chance of 

experiencing ground shaking resulting in minor damage (USGS 2020). As shown on

Figure 3.10-1, the Tier 1/Program EIS/EIR Study Area traverses multiple earthquake faults and AP 

fault zones.
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 1 of 6)
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 2 of 6)
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 3 of 6)
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 4 of 6)
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 5 of 6)
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Figure 3.10-1. Potential Seismic and Geologic Hazard Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 6 of 6)
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Build Alternative Option 1 (Coachella Terminus)

There are portions of the Build Alternative Option 1 that cross an earthquake fault or are mapped as 

being within an AP fault zone. Table 3.10-1 provides a summary of earthquake faults and AP fault 

zones located within Build Alternative Option 1.

Table 3.10-1. Summary of Earthquake Faults and Zones (Build Alternative Options 1, 2, 

and 3)

Earthquake Fault Earthquake Fault Zone

Earthquake Fault 

Zone Section County

Whittier Fault Elsinore Fault Zone Whittier Section Orange

Chino Fault Elsinore Fault Zone Chino Section Riverside

Rialto-Colton Fault San Jacinto Fault Zone

San Bernardino 

Section 

San Bernardino, 

Riverside

San Jacinto Fault San Jacinto Fault Zone

San Bernardino 

Section

San Bernardino

Loma Linda Fault San Jacinto Fault Zone

San Bernardino 

Section 

San Bernardino

Claremont Fault San Jacinto Fault Zone

San Bernardino 

Section 

San Bernardino

Live Oak Canyon Fault Crafton Hills Fault Zone — San Bernardino, 

Riverside

— Beaumont Plain Fault Zone — Riverside

Garnet Hill Fault San Andreas Fault Zone

San Bernardino 

Mountains Section

Riverside

Source: USGS 2020

Build Alternative Option 2 (Indio Terminus)

Identified earthquake faults and AP fault zones located within Build Alternative Option 2 

(Table 3.10-1) are the same as Build Alternative Option 1. 
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Build Alternative Option 3 (Indio Terminus with Limited Third Track)

Identified earthquake faults and AP fault zones located within Build Alternative Option 3

(Table 3.10-1) are the same as Build Alternative Option 1.

Seismic/Geologic Hazard Zones

Seismic or geologic hazards are natural seismic or geologic events that can endanger human lives 

and threaten property. Potential seismic or geologic hazards include liquefaction/seismically induced 

settlement, slope instability (landslide susceptibility), collapsible and expansive soils, corrosive soils, 

and subsidence. As shown on Figure 3.10-1, the Tier 1/Program EIS/EIR Study Area contains areas 

where seismic or geologic hazards zones may be present. Table 3.10-2 provides background 

information for these seismic or geologic hazards. 

Table 3.10-2. Seismic and Geologic Hazards Definitions

Seismic/Geologic 

Hazard Definition Potential Occurrence 

Liquefaction Liquefaction is the loss of soil strength or 

stiffness due to a buildup of pore-water 

pressure during ground shaking. Liquefaction is 

associated primarily with loose (low-density), 

saturated, fine- to medium-grained, 

cohesionless soils. Effects of liquefaction can 

include sand boils, excessive displacements, 

bearing capacity failures, and lateral spreading.

Liquefaction can occur primarily within 

loose to moderately dense sandy soil 

due to reduction in volume during and 

shortly after an earthquake event.

Seismically induced 

settlement

Seismically induced settlement consists of dry 

dynamic settlement (above groundwater) and 

liquefaction-induced settlement (below 

groundwater).

This settlement occurs primarily within 

loose to moderately dense sandy soil 

due to reduction in volume during and 

shortly after an earthquake event. 

Slope instability 

(landslides)

Slope instability is related to slope gradient, soil 

or rock type, consolidation or cementation of the 

rock, and the amount of fracturing of the rock.

Generally, slopes of 10 degrees or more are 

subject to seismically induced land sliding.

Land sliding can be seismically 

induced, resulting from extended 

periods of ground shaking and high 

ground accelerations. Improper 

grading and excessive rainfall or 

irrigation can also increase the 

susceptibility of land sliding. 
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Seismic/Geologic 

Hazard Definition Potential Occurrence 

Collapsible soils Collapsible soils are soils that undergo 

settlement upon wetting, even without the 

application of additional loads. Typical 

collapsible soils are low in plasticity and have 

relatively low moisture contents and densities.

Effects resulting from collapsible soils

have largely been addressed by 

county and municipal building codes. 

Expansive soils Expansive soils are generally plastic clays that 

can undergo a substantial increase in volume 

with an increase in moisture content and a 

substantial decrease in volume with a decrease 

in moisture content. Expansive soils can cause 

uplift pressures that can lead to structural 

damage.

Effects resulting from expansive soils 

have largely been addressed by 

county and municipal building codes. 

Corrosive soils Soil corrosion occurs when chemical 

compounds in the soils interact with structural 

materials in ways that weaken the materials. 

Metals are attacked by a chloride solution 

whereas concrete is typically affected by high 

sulfate levels. 

Effects resulting from corrosive soils 

have largely been addressed by 

county and municipal building codes.

Land subsidence Land subsidence, or the settling of land over 

time, can occur for a number of reasons.

Within Southern California, land 

subsistence is generally caused by 

the lowering of the water table from 

groundwater withdrawals.

Build Alternative Option 1 (Coachella Terminus)

As shown on Figure 3.10-1, the majority of the Western Section and Eastern Section of Build 

Alternative Option 1 is within a seismically induced liquefaction zone and portions are located within 

landslide susceptibility zones.

For portions of the Western Section located within southeast Los Angeles County and northwest 

Orange County, landslide susceptibility is low due to the relatively flat topography. For portions of the 

Western Section located in northeast Orange County, landslide susceptibility is moderate to high 

due to steep slopes and landslide-prone rocks. This variation in landslide susceptibility is also 

present in the Eastern Section of Build Alternative Option 1. Portions of the Eastern Section cross 

areas with relatively flat topography, resulting in a low landslide susceptibility potential. For portions 

of the Eastern Section that are located within or adjacent to steep slopes (Crafton Hills, Loma Linda 
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Hills, San Gorgonio Pass, San Timoteo Canyon, Reche Canyon), there is a moderate to high 

landslide susceptible potential. 

As shown on Figure 3.10-1, there are three USGS mapped areas of land subsidence within Build 

Alternative Option 1: Los Angeles/Santa Ana Basin subsidence area, Yucaipa Valley subsidence 

area, and Coachella Valley subsidence area. Portions of the Western Section of Build Alternative 

Option 1 that cross through Anaheim are located within the Los Angeles/Santa Ana Basin 

subsidence area, while portions that cross through Riverside and Colton are located within the 

Yucaipa Valley subsidence area. The majority of the Eastern Section of Build Alternative Option 1 is 

located in either the Yucaipa Valley or Coachella Valley subsidence areas. As identified by USGS, 

the subsidence in these areas was a result of excessive groundwater pumping in the region. 

Groundwater within these regions is an important water supply source with the demand for water 

exceeding the deliveries of imported surface water. As a result, groundwater levels have been 

declining as a result of increased pumping resulting in land subsidence in the region. To counteract 

the noted land subsidence, local and regional agencies have implemented various measures 

including the adjudication of certain groundwater basins (San Bernardino Basin and Beaumont Basin 

within the Yucaipa Valley subsidence area) and the installation off a network of continuous global 

positioning system stations to monitor subsidence (within the Coachella Valley subsidence area). 

Build Alternative Option 2 (Indio Terminus)

Potential seismic and geologic hazard zones within Build Alternative Option 2 are the same as Build 

Alternative Option 1. 

Build Alternative Option 3 (Indio Terminus with Limited Third Track)

Potential seismic and geologic hazard zones within Build Alternative Option 3 are the same as Build 

Alternative Option 1.

Paleontological Resources

Paleontological resources—or fossils—are the remains of ancient plants and animals that can 

provide scientifically significant information about the history of life on Earth. Paleontological 

sensitivity is defined as the potential for a geologic unit to produce scientifically significant fossils. 

This sensitivity is determined by rock type, history of the rock unit in producing significant fossils, and 

fossil localities that are recorded from that unit. Paleontological sensitivity is assigned based on 

fossil data collected from the entire geologic unit, not just at a specific site. Paleontological sensitivity 

(potential) ratings (Society for Vertebrate Paleontology 2010) are summarized in Table 3.10-3.
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Table 3.10-3. Paleontological Sensitivity Ratings

Sensitivity 

Potential Definition 

High sensitivity Rock units from which vertebrate or significant invertebrate, plant, or trace fossils have been 

recovered are considered to have a high potential for containing additional significant 

paleontological resources. Rocks units classified as having high potential for producing 

paleontological resources include, but are not limited to, sedimentary formations and some 

volcaniclastic formations (e.g., ashes or tephras), some low-grade metamorphic rocks that 

contain significant paleontological resources anywhere within their geographical extent, and 

sedimentary rock units temporally or lithologically suitable for the preservation of fossils (e.g., 

middle Holocene and older, fine-grained fluvial sandstones, argillaceous and carbonate-rich 

paleosols, cross-bedded point bar sandstones, fine-grained marine sandstones, etc.).

Low sensitivity This includes rock units that have low potential for yielding significant fossils. Such rock units 

will be poorly represented by fossil specimens in institutional collections. Rock units with low 

potential typically will not require impact mitigation measures to protect fossils.

Undetermined 

sensitivity 

Rock units for which little information is available concerning their paleontological content, 

geologic age, and depositional environment are considered to have undetermined potential. 

Further study is necessary to determine if these rock units have high or low potential to 

contain significant paleontological resources.

Paleontological resources are considered non-renewable resources because they are the remains of 

prehistoric animal and plant life.

Given the diversity of geologic units found within the Tier 1/Program EIS/EIR Study Area, the 

paleontology is equally diverse, and, in some areas, fossil resources are abundant. A detailed 

analysis of the paleontological sensitivity of each geologic formation within the Tier 1/Program 

EIS/EIR Study Area is beyond the scope of the Tier 1/Program-level analysis and would be the 

subject of Tier 2/Project-level paleontological assessments. A generalized description of regional 

paleontological settings has been provided below. 

In the western portion of Riverside County, fossils occur in sediments lying on the surface of 

crystalline bedrock or are deposited in or between the major fault zones. The eastern desert portions 

of Riverside County are marked by fault block mountains that contain older fossil-bearing sediments 

with younger fossil-containing deposits found around dry lakes, along high stands of the Salton Sea 

and in terraces left by the Colorado River.
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The oldest fossils in California are from the Proterozoic Age, dating to 900 million years ago. 

However, no fossils from the Proterozoic Age are currently known to occur in Riverside County. It is 

thought that in this area of Southern California, fossils earlier than the Jurassic Period may have 

been destroyed by the natural processes of metamorphism (geological changes in the rocks and 

soils). The oldest fossils found in Riverside County date to the Late Jurassic Period (approximately 

150 million years ago) (Riverside County Planning Department 2015). 

Figure 3.10-2 shows areas of potential paleontological sensitivity within the Tier 1/Program EIS/EIR 

Study Area. 
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 1 of 6)
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 2 of 6)
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 3 of 6)
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 4 of 6)
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 5 of 6)
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Figure 3.10-2. Paleontological Sensitivity within the Tier 1/Program EIS/EIR Study Area 

(Sheet 6 of 6)
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Build Alternative Option 1 (Coachella Terminus)

For the Western Section of Build Alternative Option 1, approximately 3,146.30 acres were identified 

as areas mapped as having high paleontological sensitivity. For the Eastern Section of Build 

Alternative Option 1, approximately 1,772.31 acres were identified as areas mapped as having high 

paleontological sensitivity. Table 3.10-4 provides a summary of high, low, and undetermined

paleontological sensitivity zones within Build Alternative Option 1.

Table 3.10-4. Summary of Paleontological Sensitivity Zones (Build Alternative Option 1)

Paleontological Sensitivity Zone

Area of Zone 

within Western 

Section (acres)

Area of Zone 

within Eastern 

Section

(acres)

Total Area of Zone 

(acres)

High 3,146.30 1,772.31 4,918.61

Low 364.80 13,404.10 13,768.90

Undetermined 2.49 2,279.15 2,281.64

Build Alternative Option 2 (Indio Terminus)

Table 3.10-5 provides a summary of paleontological resource zones within Build Alternative Option 

2. There are fewer acres of paleontological resource zones within Build Alternative Option 2 because 

of the shorter route alignment and reduced station options. 

Table 3.10-5. Summary of Paleontological Sensitivity Zones (Build Alternative Options 2 

and 3)

Paleontological Sensitivity Zone

Area of Zone 

within Western 

Section (acres)

Area of Zone 

within Eastern 

Section 

(acres)

Total Area of Zone 

(acres)

High 3,146.30 706.77 3,853.07

Low 364.80 13,404.10 13,768.90

Undetermined 2.49 2,279.15 2,281.64

Build Alternative Option 3 (Indio Terminus with Limited Third Track)

Potential paleontological sensitivity areas within Build Alternative Option 3 are the same as Build 

Alternative Option 2.
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Mineral Resources

Minerals are defined as any naturally occurring chemical elements or compounds, formed from 

inorganic processes and organic substances. Mineable minerals or an ore deposit is defined as a 

deposit of ore or mineral having a value materially in excess of the cost of developing, mining, and 

processing the mineral and reclaiming the project area. The conservation, extraction, and processing 

of mineral resources are an integral part of development and economy within Southern California.

The CGS provides information about California’s non-fuel mineral resources and classifies lands 

throughout the state that contain regionally significant mineral resources, as mandated by the

Surface Mining and Reclamation Act. Non-fuel mineral resources include metals such as gold, silver, 

iron, and copper; industrial metals such as boron compounds, rare-earth elements, clays, limestone, 

gypsum, salt, and dimension stone; and construction aggregate such as sand, gravel, and crushed 

stone. Development generally results in a demand for minerals, especially construction aggregate. 

The classification of these mineral resources is a joint effort of the state and the local governments

and is based on geologic factors and requires that the State Geologist classify the mineral resources 

area as one of the four MRZs, as summarized in Table 3.10-6. 

Table 3.10-6. Mineral Resource Zone Ratings

MRZ Definition 

MRZ-1 Areas where adequate information indicates that no significant mineral deposits are present 

or likely to be present

MRZ-2 Areas where adequate information indicates that significant mineral deposits are present or a 

high likelihood exists for their presence

Subcategory MRZ-2a indicates measured/indicated mineral resource reserves, while 

Subcategory MRZ-2b indicates inferred mineral resources

MRZ-3 Areas where the significance of mineral deposits cannot be determined from available data

MRZ-4 Areas where available information is inadequate for assignment to any other MRZ 

designation

Source: USGS 2020

Notes:

MRZ=mineral resource zone

As shown on Figure 3.10-3, the Tier 1/Program EIS/EIR Study Area traverses multiple MRZs. 
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 1 of 6)
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 2 of 6)
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 3 of 6)
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 4 of 6)
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 5 of 6)
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Figure 3.10-3. Mineral Resource Zones within the Tier 1/Program EIS/EIR Study Area 

(Sheet 6 of 6)
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Build Alternative Option 1 (Coachella Terminus)

For the Western Section of Build Alternative Option 1, the largest type of MRZ mapped land is 

MRZ-3 (5,911.9 acres). Other land mapped as MRZ-1 and MRZ-2 are also present within the 

Western Section. For the Eastern Section of Build Alternative Option 1, the largest type of MRZ

mapped land is MRZ-3 (13,550.5 acres). Other land mapped as MRZ-1 and MRZ-2 are also present 

within the Eastern Section. 

Two active mines are identified within the Eastern Section: the Cabazon Quarry and the Garnet Site. 

As shown on Figure 3.10-3, the Cabazon Quarry, owned and operated by Robertson’s Ready Mix, is 

located within the Pass Area Station Area with the primary mineral resources mined being sand and 

gravel. The Garnet Site, owned and operated by Granite Construction Company, is located between 

the Pass Area Station Area and Mid-Valley Station Area with the primary mineral resources mined

being sand and gravel. Table 3.10-7 provides a summary of MRZs within Build Alternative Option 1.

Table 3.10-7. Summary of Mineral Resource Zones (Build Alternative Option 1)

MRZ

Area of Zone 

within Western 

Section (acres)

Area of Zone 

within Eastern 

Section (acres)

Total Area of Zone 

(acres)

MRZ-1 2,660.2 5,445.7 8,105.8

MRZ-2 1,535.0 2,654.3 4,189.3

MRZ-3 5,911.9 13,550.5 19,462.4

MRZ-4 0.0 0.0 0.0

Source: USGS 2020

Notes:

MRZ=mineral resource zone

Build Alternative Option 2 (Indio Terminus)

For the Western Section of Build Alternative Option 2, the largest type of MRZ mapped land is 

MRZ-3 (5,911.9 acres). Other land mapped as MRZ-1 and MRZ-2 are also present within the 

Western Section. For the Eastern Section of Build Alternative Option 1, the largest type of MRZ

mapped land is MRZ-3 (13,550.5 acres). Other land mapped as MRZ-1 and MRZ-2 are also present 

within the Eastern Section. 

Two active mines are identified within the Eastern Section: the Cabazon Quarry and the Garnet Site. 

Table 3.10-8 provides a summary of MRZs within Build Alternative Option 2.
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There are fewer acres of MRZs within Build Alternative Option 2 because of the shorter route 

alignment and reduced station options. 

Table 3.10-8. Summary of Mineral Resource Zones (Build Alternative Options 2 and 3)

MRZ

Area of MRZ within 

Western Section 

(acres)

Area of MRZ

within Eastern 

Section (acres)

Total Area of MRZ

(acres)

MRZ-1 2,660.2 4574.9 7,235.1

MRZ-2 1,535.0 2,654.3 4,189.3

MRZ-3 5,911.9 13,550.5 19,462.4

MRZ-4 0.0 0.0 0.0

Source: USGS 2020

Notes:

MRZ=mineral resource zone

Build Alternative Option 3 (Indio Terminus with Limited Third Track)

MRZs within Build Alternative Option 3 (Table 3.10-8) are the same as Build Alternative Option 2.

3.10.5 Environmental Consequences

Overview

Effects as a result of implementing the Build Alternative Options can be broadly classified into 

construction and operational effects. Long-term or permanent effects and short-term or temporary 

effects related to geology, soils, seismicity, mineral resources, and paleontological resources would 

be anticipated as a result of constructing any of the Build Alternative Options. 

Most effects related to geology, soils, mineral resources, and paleontological resources would occur 

during construction when the ground is disturbed, and grading and excavation activities could result 

in impacts on buried resources. Potential impacts resulting from seismic activity in the Tier 

1/Program EIS/EIR Study Area would be more likely to occur during operation over the course of the 

Program’s lifespan. 

No Build Alternative

The No Build Alternative, as described in Chapter 2, Program Alternatives, is used as the baseline 

for comparison. The No Build Alternative would not implement the Program associated with this 

service-level evaluation. Because no physical changes associated with the Program would occur, no 
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effects on geology, soils, seismicity, and paleontological and mineral resources are anticipated

under the No Build Alternative. However, due to the seismic nature of Southern California, geologic 

hazards such as seismically induced fault rupture, ground shaking, landslides, and liquefaction may 

still occur under the No Build Alternative.

Build Alternative Options 1, 2, and 3

Seismic/Geologic Hazard Effects

CONSTRUCTION

Western Section. The Build Alternative Options would not require construction of additional rail or 

station infrastructure in the Western Section of the Program Corridor because the existing railroad 

ROW, and stations from LAUS to Colton would be used. When compared with the No Build 

Alternative, effects would be negligible because no additional construction activities are planned 

within the Western Section under Build Alternative Options 1, 2, and 3. 

Eastern Section. Construction of Build Alternative Option 1, 2, or 3 in the Eastern Section of the 

Program Corridor would require the construction of rail stations, reconfiguration of existing or 

creation of new rail facilities, and potential ROW acquisition. If a passenger rail system is 

constructed and operated within the existing rail ROW, no ROW acquisitions would be required. 

However, the Tier 1/Program EIS/EIR Study Area allows for infrastructure and station facilities to be 

located beyond the limits of the existing rail ROW, which would require acquisition of land that could 

be within a potential seismic or geologic hazard zone. 

Soil types and geologic formations are indications of stability for Program infrastructure and facilities 

and longevity of service. Soils with high clay content often have high shrink/swell potential and are 

generally poorly suited for railway, road, or foundation bases. Such soils may need to be excavated 

and replaced prior to construction or treated in place to limit effects on proposed structures. 

Construction activities may also disturb or modify soils and slopes and must be managed through 

standard engineering practices and design to avoid and minimize potential risk. Additionally, some 

portions of the Eastern Section traverse areas with moderate to high susceptibility to landslides and 

liquefaction.

While applicable building codes and design features to address potential seismic or geologic 

hazards would be adhered to and developed, potential effects depend on where the infrastructure 

improvements, including new stations, which have not yet been selected, would be located. Which 

properties would be affected by the future construction and operation of a passenger rail system, 

and to what extent, cannot be determined at this time. The Tier 2/Project-level analysis would 
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evaluate the selected site and proposed infrastructure improvement or station facility and whether 

people or structures are exposed to increased seismic or geologic hazard risk. 

When compared with the No Build Alternative, Build Alternative Option 1 could have a moderate 

effect associated with seismic or geologic hazard zones within the Eastern Section of the Program 

Corridor. When compared with Build Alternative Option 1, Build Alternative Option 2 may have 

slightly reduced effects due to a smaller footprint associated with a shorter route alignment and

reduced station options; however, the magnitude of effects would be similar and would be 

considered moderate when compared with the No Build Alternative. When compared with Build 

Alternative Options 1 or 2, Build Alternative Option 3 may have slightly reduced effects due to a 

smaller footprint associated with a shorter route alignment, reduced station options, and reduced 

third track rail infrastructure. However, the magnitude of effects would be similar for Build Alternative 

Option 3 and would be considered moderate when compared with the No Build Alternative.

OPERATION 

Western Section. Operation of Build Alternative Option 1, 2, or 3 within the Western Section would 

not result in new effects associated with seismic or geologic hazards, as the additional train trips 

would travel within an existing railroad ROW. When compared with the No Build Alternative, effects 

associated with seismic or geologic hazards would be negligible because no additional infrastructure 

improvements are planned within the Western Section under Build Alternative Options 1, 2, and 3.

Eastern Section. The Build Alternative Options cross AP fault zones capable of ground rupture and 

would be generally susceptible to earthquakes resulting in ground shaking. Additionally, some 

portions of the Eastern Section traverse areas with moderate to high susceptibility to landslides and 

liquefaction. Operation would comply with federal, state, and, local design and safety criteria 

regarding structural integrity to protect the public and property from geologic, soil, and seismic 

hazards. The Tier 2/Project-level analysis would evaluate site-specific impacts associated with 

seismic or geologic hazard areas and whether operation of a facility would result in effects on the 

public.

When compared with the No Build Alternative, Build Alternative Option 1 could have a moderate 

effect on seismic or geologic hazards within the Eastern Section of the Program Corridor. When 

compared with Build Alternative Option 1, Build Alternative Option 2 would have slightly reduced 

effects due to a shorter route alignment and reduced station options. However, the magnitude of 

effects would be similar and would be considered moderate when compared with the No Build 

Alternative. When compared with Build Alternative Options 1 2, Build Alternative Option 3 may have 

slightly reduced effects due to a smaller footprint associated with a shorter route alignment, reduced 

station options, and reduced third track rail infrastructure. However, the magnitude of effects would 
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be similar for Build Alternative Option 3 and would be considered moderate when compared with the 

No Build Alternative.

Paleontological Resource Effects

CONSTRUCTION 

Western Section. The Build Alternative Options would not require construction of additional rail or 

station infrastructure in the Western Section of the Program Corridor because the existing railroad,

and stations from LAUS to Colton would be used. When compared with the No Build Alternative, 

short-term/temporary effects associated with the paleontological resources would be negligible 

because no additional construction activities are planned within the Western Section under Build 

Alternative Options 1, 2, and 3.

Eastern Section. Construction of Build Alternative 1, 2, or 3 in the Eastern Section of the Program 

Corridor would require the construction of rail stations, reconfiguration of existing or creation of new 

rail facilities, and potential ROW acquisition. These construction activities could occur in areas 

identified as having undetermined or high paleontological sensitivity. Direct physical effects on 

paleontological resources may include damage or destruction during ground-disturbing activities 

associated with construction of rail infrastructure improvements or station facilities.

Excavation of the sediments within a high paleontological sensitivity area could destroy or degrade 

the condition of the fossil. Additionally, the nature of excavation activities would cause any fossils to 

be removed from their stratigraphic context, thereby reducing the scientific usefulness of the fossil. 

Paleontological resources are considered a finite and unique resource. Once disturbed or removed, 

that resource is effectively eliminated. When compared with the No Build Alternative, Build 

Alternative Option 1 could have a substantial effect on paleontological resources within the Eastern 

Section of the Program Corridor. When compared with Build Alternative Option 1, Build Alternative 

Option 2 would have slightly reduced effects due to a shorter route alignment and reduced station 

options. However, the magnitude of effects would be similar and considered substantial when 

compared with the No Build Alternative. When compared with Build Alternative Options 1 or 2, Build 

Alternative Option 3 may have slightly reduced effects due to a smaller footprint associated with a 

shorter route alignment, reduced station options, and reduced third track rail infrastructure. However, 

the magnitude of effects would be similar for Build Alternative Option 3 and would be considered 

substantial when compared with the No Build Alternative. However, detailed analysis of ROW 

acquisition impacts would be completed in a Tier 2/Project-level analysis.
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OPERATION

Western Section. Operation of Build Alternative Option 1, 2, or 3 within the Western Section would 

not result in new effects associated with paleontological resources, as the additional train trips would 

travel within an existing railroad ROW. When compared with the No Build Alternative, effects 

associated with paleontological resources would be negligible because no additional infrastructure 

improvements are planned within the Western Section under Build Alternative Options 1, 2, and 3.

Eastern Section. Once construction ceases, operation of the new railroad infrastructure and stations 

under the Build Alternative Options are not anticipated to result in changes associated with 

paleontological resources. Operational effects associated with the Eastern Section of Build 

Alternative Option 1 would be negligible when compared with the No Build Alternative. When 

compared with Build Alternative Option 1, Build Alternative Option 2 would have the same 

magnitude of effect and be considered negligible when compared with the No Build Alternative.

When compared with Build Alternative Options 1 or 2, Build Alternative Option 3 may have slightly 

reduced effects due to a smaller footprint associated with a shorter route alignment, reduced station 

options, and reduced third track rail infrastructure. However, the magnitude of effects would be 

similar for Build Alternative Option 3 and would be considered negligible when compared with the No 

Build Alternative.

Mineral Resource Effects

CONSTRUCTION

Western Section. Operation of Build Alternative Option 1, 2, or 3 within the Western Section would 

not result in effects on mineral resources, as the additional train trips would travel within an existing 

railroad ROW. When compared with the No Build Alternative, effects on mineral resources would be 

negligible because no additional infrastructure improvements are planned within the Western 

Section under Build Alternative Options 1, 2, and 3.

Eastern Section. Construction of Build Alternative 1, 2, or 3 in the Eastern Section of the Program 

Corridor would require the construction of rail stations, reconfiguration of existing or creation of new 

rail facilities, and potential ROW acquisition. These would require the conversion of 

non-transportation land to a transportation use. The site-specific design that would be developed in 

later Program phases would determine the extent to which land use conversions occur. If the rail 

infrastructure or station facility is within the ROW of, or closely parallel to, an existing transportation 

corridor, the extent of land conversion would be minimal. However, the further rail infrastructure or a 

station facility departs from an existing transportation feature, the greater the likelihood for land use 

conversion, ranging from building on vacant/undeveloped land to potential displacement of existing 

structures.
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If a passenger rail system is constructed and operated within the existing rail ROW, no ROW 

acquisitions would be required. However, the Tier 1/Program EIS/EIR Study Area allows for 

infrastructure and station facilities to be located beyond the limits of the existing rail ROW, which 

would require acquisition of land not designated for transportation uses. Which mineral resources 

would be affected by the future construction and operation of a passenger rail system, and to what 

extent, cannot be determined at this time. 

If MRZ mapped lands within the Eastern Section of the Program Corridor are converted to a 

transportation use, it would be considered an adverse effect. Mineral resource lands are considered 

a finite and unique resource; once mineral resource land is converted to other uses, that resource is 

effectively eliminated. When compared with the No Build Alternative, Build Alternative Option 1 could 

have a substantial effect on mineral resources within the Eastern Section of the Program Corridor. 

When compared with Build Alternative Option 1, Build Alternative Option 2 would have slightly 

reduced effects due to a shorter route alignment and reduced station options. However, the 

magnitude of effects would be similar and considered substantial when compared with the No Build 

Alternative. When compared with Build Alternative Options 1 or 2, Build Alternative Option 3 may 

have slightly reduced effects due to a smaller footprint associated with a shorter route alignment, 

reduced station options, and reduced third track rail infrastructure. However, the magnitude of 

effects would be similar for Build Alternative Option 3 and would be considered substantial when 

compared with the No Build Alternative. However, detailed analysis of ROW acquisition impacts 

would be completed in a Tier 2/Project-level analysis.

OPERATION

Western Section. Operation of Build Alternative Option 1, 2, or 3 within the Western Section would 

not result in new effects associated with mineral resources or mineral resource sites, as the 

additional train trips would travel within an existing railroad ROW. When compared with the No Build 

Alternative, effects associated with mineral resources would be negligible because no additional 

infrastructure improvements are planned within the Western Section under Build Alternative Options 

1, 2, and 3.

Eastern Section. Once construction ceases, operation of the new railroad infrastructure and stations 

under the Build Alternative Options are not anticipated to result in changes associated with mineral 

resources or mineral resource sites. Operational effects associated with the Eastern Section of Build 

Alternative Option 1 would be negligible when compared with the No Build Alternative. When 

compared with Build Alternative Option 1, Build Alternative Option 2 would have the same 

magnitude of effect and be considered negligible when compared with the No Build Alternative.

When compared with Build Alternative Options 1 or 2, Build Alternative Option 3 may have slightly 

reduced effects due to a smaller footprint associated with a shorter route alignment, reduced station 
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options, and reduced third track rail infrastructure. However, the magnitude of effects would be 

similar for Build Alternative Option 3 and would be considered negligible when compared with the No 

Build Alternative.

3.10.6 NEPA Summary of Potential Effects

Table 3.10-9 through Table 3.10-11 summarizes the qualitative assessment of potential effects 

(negligible, moderate, or substantial) under NEPA for each of the Build Alternative Options. This 

service-level evaluation uses the Tier 1/Program EIS/EIR Study Area to determine the relative 

magnitude of potential effects on geology, soils, seismicity, paleontological resources, and mineral 

resources under each of the Build Alternative Options. Specific mitigation measures to reduce 

effects would be identified during the Tier 2/Project-level analysis.

Table 3.10-9. NEPA Summary of Effects on Seismic and Geologic Hazards

Alternative Option

Potential Intensity of Effect: 

Western Section

Potential Intensity of Effect: 

Eastern Section

No Build Alternativea Construction: None 

Operation: None 

Construction: None

Operation: None 

Build Alternative Option 1 

(Coachella Terminus)

Construction: Negligible 

Operation: Negligible

Construction: Moderate

Operation: Moderate 

Build Alternative Option 2 

(Indio Terminus)

Construction: Negligible 

Operation: Negligible

Construction: Moderate

Operation: Moderate 

Build Alternative Option 3 

(Indio Terminus with Limited Third 

Track)

Construction: Negligible 

Operation: Negligible

Construction: Moderate

Operation: Moderate

Notes:

a The No Build Alternative includes existing and potential expansion of roadway, passenger rail, and air travel 

facilities within the Tier 1/Program EIS/EIR Study Area; however, for the service-level evaluation, identifying levels 

of effect from potential expansion of those facilities is speculative and would be dependent on Project-specific 

analysis.
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Table 3.10-10. NEPA Summary of Effects on Paleontological Resources

Alternative Option

Potential Intensity of Effect: 

Western Section

Potential Intensity of Effect: 

Eastern Section

No Build Alternativea Construction: None 

Operation: None 

Construction: None

Operation: None 

Build Alternative Option 1 

(Coachella Terminus)

Construction: Negligible 

Operation: Negligible

Construction: Substantial

Operation: Negligible 

Build Alternative Option 2 

(Indio Terminus)

Construction: Negligible

Operation: Negligible

Construction: Substantial

Operation: Negligible 

Build Alternative Option 3 

(Indio Terminus with Limited 

Third Track)

Construction: Negligible

Operation: Negligible

Construction: Substantial

Operation: Negligible

Notes:

a The No Build Alternative includes existing and potential expansion of roadway, passenger rail, and air travel 

facilities within the Tier 1/Program EIS/EIR Study Area; however, for the service-level evaluation, identifying levels 

of effect from potential expansion of those facilities is speculative and would be dependent on Project-specific 

analysis.

Table 3.10-11. NEPA Summary of Effects on Mineral Resources

Alternative Option

Potential Intensity of Effect: 

Western Section

Potential Intensity of Effect: 

Eastern Section

No Build Alternativea Construction: None 

Operation: None 

Construction: None

Operation: None 

Build Alternative Option 1 

(Coachella Terminus)

Construction: Negligible 

Operation: Negligible

Construction: Substantial

Operation: Negligible

Build Alternative Option 2 

(Indio Terminus)

Construction: Negligible 

Operation: Negligible

Construction: Substantial

Operation: Negligible 
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Alternative Option

Potential Intensity of Effect: 

Western Section

Potential Intensity of Effect: 

Eastern Section

Build Alternative Option 3 

(Indio Terminus with Limited Third 

Track)

Construction: Negligible 

Operation: Negligible

Construction: Substantial

Operation: Negligible

Notes:

a The No Build Alternative includes existing and potential expansion of roadway, passenger rail, and air travel 

facilities within the Tier 1/Program EIS/EIR Study Area; however, for the service-level evaluation, identifying levels 

of effect from potential expansion of those facilities is speculative and would be dependent on Project-specific 

analysis.

3.10.7 CEQA Summary of Potential Impacts

Based on the information provided in Section 3.10.4 and 3.10.5, and considering the CEQA 

Guidelines Appendix G Checklist questions for geology, soils, paleontological resources, and 

mineral resources, the Build Alternative Options would have a potentially significant impact on 

geology, soils, paleontological resources, and mineral resources when reviewed on a Program-wide 

basis. Placing the infrastructure improvements and new stations largely within or along the existing 

ROW reduces the potential for significant impacts on these resources; however, because the sites 

have not been selected, some resources may be significantly impacted. At the programmatic 

analysis level, it is not possible to know the location, extent, and characteristics of impacts on these 

resources. Proposed programmatic mitigation strategies discussed in Section 3.10.8 would be 

applied to reduce potential impacts. 

Table 3.10-12 summarizes the CEQA significance conclusions for the Build Alternative Options; the 

proposed programmatic mitigation strategies that could be applied to minimize, reduce, or avoid the 

potential impacts; and the significance determination after mitigation strategies are applied. The 

identification and implementation of additional site-specific mitigation measures necessary for 

Project implementation would occur as part of the Tier 2/Project-level analysis. 
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Table 3.10-12. CEQA Summary of Impacts for Geology, Soils, and Mineral Resources

Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Would the Program directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury or death involving

rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State 

Geologist for the area or based on other substantial evidence of a known fault? 

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable 

Eastern Section – Potentially Significant. Potential exposure to seismic 

hazards during construction activities are dependent on the location of rail 

infrastructure improvements and station facilities, which are currently 

unknown. Build Alternative Options 1, 2, and 3 cross areas where identified 

earthquake faults and AP fault zones are present; therefore, there is 

potential for significant impacts. The Tier 2/Project-level analysis would 

evaluate the potential of seismic risk and whether people or structures would 

be exposed to significant seismic risk during construction activities.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts associated with 

construction activities within areas containing potential 

seismic hazards through design and further analysis 

during the Tier 2/Project-level environmental process. 

Operation

Western Section – Less Than Significant. The Western Section of the 

Program Corridor is subject to seismic ground shaking due to the existing 

geologic conditions in Southern California. The increased train service (two 

additional round-trip daily trains within the Program Corridor) would not 

change existing land use and would not result in new seismic hazards to the 

public or the environment. Therefore, a less than significant impact under 

Build Alternative Option 1, 2, or 3 is anticipated at the Tier 1/Program 

EIS/EIR evaluation level.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – Potentially Significant. Once construction ceases, 

operation of the new railroad infrastructure and stations under the Build 

Alternative Options are not anticipated to result in changes associated with 

seismic hazard zones. However, the operation of new station facilities within 

seismic hazard zones could result in an increased seismic hazard risks to 

people or structures in the area; therefore, there is potential for significant 

impacts. The Tier 2/Project-level analysis would evaluate the potential for 

people or structures to be exposed to seismic hazards during operation. 

LU-3 Less than Significant. LU-3 would minimize, reduce, 

or avoid potential impacts on people and structures 

resulting from seismic hazards through design and 

further analysis during the Tier 2/Project-level

environmental process.

Would the Program directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury or death involving 

strong seismic ground shaking?

Construction

Western Section – No Impact. Although the Western Section of the 

Program Corridor would be subject to seismic ground shaking, no 

construction impacts are anticipated at the Tier 1/Program EIS/EIR 

evaluation level under Build Alternative Option 1, 2, or 3 because no physical 

improvements are proposed or required within the Western Section.

Not applicable Not applicable 

Eastern Section – Potentially Significant. Potential exposure to strong 

seismic shaking during construction activities are dependent on the location 

of rail infrastructure improvements and station facilities, which are currently 

unknown. Build Alternative Options 1, 2, and 3 cross areas where strong 

seismic shaking could occur; therefore, there is potential for significant 

impacts. The Tier 2/Project-level analysis would evaluate the potential of 

seismic risk and whether people or structures would be exposed to 

significant seismic risk during construction activities.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts associated with 

construction activities within areas subject to strong 

seismic ground shaking through design and further 

analysis during the Tier 2/Project-level environmental 

process. 
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Operation

Western Section – Less Than Significant. The Western Section of the 

Program Corridor is subject to seismic ground shaking due to the existing 

geologic conditions in Southern California. The increase in train service (two 

additional round-trip daily trains within the Program Corridor) would not 

change existing land use and would not result in new seismic hazards to the 

public or the environment. Therefore, a less than significant impact under 

Build Alternative Option 1, 2, or 3 is anticipated at the Tier 1/Program 

EIS/EIR evaluation level.

Not applicable Not applicable

Eastern Section – Potentially Significant. Once construction ceases, 

operation of the new railroad infrastructure and stations under the Build 

Alternative Options are not anticipated to result in changes associated with 

seismic hazard zones. However, the operation of new station facilities within 

seismic hazard zones could result in an increased seismic hazard risks to 

people or structures in the area; therefore, there is potential for significant 

impacts. The Tier 2/Project-level analysis would evaluate the potential for 

people or structures to be exposed to seismic hazards during operation. 

LU-3 Less than Significant. LU-3 would minimize, reduce, 

or avoid potential impacts on people and structures 

resulting from seismic hazards through design and 

further analysis during the Tier 2/Project-level 

environmental process.

Would the Program directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury or death involving 

seismic-related ground failure, including liquefaction?

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable 
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – Potentially Significant. Potential impacts from 

seismic-related ground failure are dependent on the location of rail 

infrastructure improvements and station facilities, which are currently 

unknown. Numerous faults and areas of high susceptibility to liquefaction are 

located within Build Alternative Options 1, 2, and 3. These seismic hazard 

areas would be considered during design with proposed infrastructure and 

structures required to adhere to all California Building Code requirements to 

address seismic safety. However, until a site-specific Project is identified, it is 

unknown if impacts would be significant. The Tier 2/Project-level analysis 

would identify and analyze site-specific impacts associated with 

seismic-related ground failure.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts related to 

seismic-related ground failure through design and 

further analysis during the Tier 2/Project-level

environmental process.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in an exacerbation of liquefaction risks or 

hazards. Therefore, no impacts are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Eastern Section – No Impact. Once construction ceases, operation of the 

new railroad infrastructure and stations under the Build Alternative Options 

are not anticipated to result in changes associated with liquefaction 

conditions. Therefore, no impacts are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Would the Program directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury or death involving 

landslides?

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable 

Eastern Section – Potentially Significant. Potential construction impacts 

resulting from landslides are dependent on the location of rail infrastructure 

improvements and station facilities, which are currently unknown. For 

construction activities that would occur in areas of high landslide 

susceptibility, there is an increased risk of landslide impacts due to increased 

human activity (e.g., movement of soils). The Tier 2/Project-level analysis 

would evaluate the potential of landslide risk and whether people or 

structures would be exposed to significant landslide risk during construction 

activities.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts related to landslide 

hazards through design and further analysis during 

the Tier 2/Project-level environmental process.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in an exacerbation of landslide risks or 

hazards. Therefore, no operational impacts are anticipated at the Tier 

1/Program EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – Potentially Significant. Once construction ceases, 

operation of the new railroad infrastructure and stations under Build 

Alternative Option 1, 2, or 3 are not anticipated to result in changes 

associated with landslide hazard zones. However, the operation of new 

station facilities within landslide hazard zones could result in an increased 

landslide risk to people or structures in the area; therefore, there is potential 

for significant impacts. The Tier 2/Project-level analysis would evaluate the 

potential for people or structures to be exposed to landslide risk during 

operation. 

LU-3 Less than Significant. LU-3 would minimize, reduce, 

or avoid potential impacts on people and structures 

resulting from landslides through design and further 

analysis during the Tier 2/Project-level environmental 

process.

Would the Program result in substantial soil erosion or the loss of topsoil?

Construction

Western Section – No Impact. No construction impacts anticipated at the 

Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 2, 

or 3 because no physical improvements are proposed or required within the 

Western Section.

Not applicable Not applicable

Eastern Section – Potentially Significant. Construction activities 

associated with rail infrastructure improvements or station facilities under 

Build Alternative Option 1, 2, or 3 would include clearing, grading, and 

excavation, which have the potential to result in soil erosion; therefore, there 

is potential for significant impacts. The Tier 2/Project-level analysis would 

identify and evaluate impacts associated with site-specific drainage patterns 

changes and the potential for site-specific construction activities to result in 

soil erosion and loss of topsoil.

HWQ-2

LU-3

Less than Significant. HWQ-2 and LU-3 would 

minimize, reduce, or avoid potential impacts related to 

soil erosion or topsoil loss by requiring compliance 

with applicable regulations. BMPs would be identified 

to minimize, reduce or, avoid potential impacts from 

erosion or siltation.
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) on an existing rail corridor 

would require maintenance of existing infrastructure. However, these 

maintenance activities do not require the alteration of existing drainage 

patterns or the addition of new impervious surfaces. Therefore, no impacts 

associated with soil erosion or loss of topsoil are anticipated at the Tier 

1/Program EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Eastern Section – No Impact. Operational activities would consist of 

ongoing maintenance of existing infrastructure and would not require the 

alteration of existing drainage patterns or the addition of new impervious 

surfaces once construction is complete. Therefore, no impacts associated 

with soil erosion or loss of topsoil are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Would the Program be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the Program and 

potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse?

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – Potentially Significant. Potential impacts are dependent 

on the location of rail infrastructure improvements or station facilities, which 

are currently unknown. These facilities and infrastructure could be located 

within an area containing unstable soil characteristics that could result in 

seismic hazards. These seismic hazard areas would be considered during 

Project design with proposed infrastructure and structures required to adhere 

to all California Building Code requirements to address seismic safety. 

However, until a site-specific Project is identified, it is unknown if impacts 

would be significant. The Tier 2/Project-level analysis would identify and 

mitigate site-specific impacts associated with seismic-related ground failure.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts related to unstable 

soil through design and further analysis during the Tier 

2/Project-level environmental process.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in impacts associated with unstable soils. 

Therefore, no impacts are anticipated at the Tier 1/Program EIS/EIR 

evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Eastern Section – No Impact. Once construction ceases, operation of the 

new railroad infrastructure and stations under the Build Alternative Options 

are not anticipated to result in changes associated with unstable soil 

conditions. Therefore, no impacts are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Would the Program be located on expansive soil, as defined in Table 18-1-B of the UBC (1994), creating substantial direct or indirect risk to 

life or property?

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable

Eastern Section – Potentially Significant. Potential impacts under Build 

Alternative Option 1, 2, or 3 related to expansive soil are dependent on the 

location of rail infrastructure improvements and station facilities, which are 

currently unknown. The Tier 2/Project-level analysis would identify and 

mitigate impacts associated with expansive soils.

GEO-1 Less than Significant. GEO-1 would minimize, 

reduce, or avoid potential impacts related to 

expansive soil through design and further analysis 

during the Tier 2/Project-level environmental process.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in expansive soil hazards. Therefore, no 

impacts are anticipated at the Tier 1/Program EIS/EIR evaluation level under 

Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Eastern Section – No Impact. Once construction ceases, operation of the 

new railroad infrastructure and stations under the Build Alternative Options 

are not anticipated to result in changes associated with expansive soils. 

Therefore, no impacts are anticipated at the Tier 1/Program EIS/EIR 

evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Would the Program have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where 

sewers are not available for the disposal of wastewater?

Construction

Western Section – No Impact. No construction impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3 because no physical improvements are proposed or required within 

the Western Section.

Not applicable Not applicable

Eastern Section – No Impact. During construction activities, the contractor 

would provide portable toilets on site, which would then be removed from the 

site on a regular basis for off-site servicing at an approved wastewater 

handling facility. Therefore, the use of alternative wastewater disposal 

systems are not anticipated during construction. No construction impacts 

associated with alternative wastewater disposal systems are anticipated 

under Build Alternative Option 1, 2, or 3 at the Tier 1/Program EIS/EIR 

evaluation level. 

Not applicable Not applicable

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use that would result in the need for alternative wastewater disposal 

systems. Therefore, no impacts are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – No Impact. Operation of the Program under Build 

Alternative Option 1, 2, or 3 would require continual maintenance rail 

infrastructure and station facilities. The operation of maintenance and station 

facilities would generate wastewater; however, it is anticipated that these 

facilities would be connected to the local wastewater facility system and not 

to septic tanks or alternative wastewater disposal systems. Therefore, no 

impacts are anticipated at the Tier 1/Program EIS/EIR evaluation level under 

Build Alternative Option 1, 2, or 3.

Not applicable Not applicable 

Would the Program directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?

Construction

Western Section – No Impact. Destruction of a unique paleontological 

resource or geologic feature would not occur because no physical 

improvements are proposed or required within the Western Section. 

Therefore, no impacts are anticipated at the Tier 1/Program EIS/EIR 

evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable

Eastern Section – Potentially Significant. Potential impacts on 

paleontological resources depend on the location of rail infrastructure 

improvements, station facilities, and the types of construction activities, 

which are currently unknown. The Eastern Section contains multiple areas of 

high paleontological sensitivity with the potential for subsurface resources to 

exist. Therefore, potentially significant impacts under Build Alternative Option 

1, 2, or 3 are anticipated at the Tier 1/Program EIS/EIR evaluation level.

PAL-1

LU-3

Potentially Significant. PAL-1 and LU-3 would 

minimize, reduce, or avoid potential impacts on 

paleontological resources through design, further 

analysis, and the avoidance of resources. However, it 

is unknown to what extent and type of impact on 

paleontological resources would occur. Impacts may 

remain significant and unavoidable if further analysis 

determines that a non-renewable paleontological 

resource would be impacted by the rail infrastructure 

improvement or station facility proposed. 
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in the destruction of a unique paleontological 

resource or site or unique geologic feature within the Western Section of the 

Program Corridor. Therefore, no impacts are anticipated at the Tier 

1/Program EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable

Eastern Section – No Impact. Once construction is complete, operation of 

Build Alternative Option 1, 2, or 3 would not result impacts on paleontological 

resources within the Eastern Section of the Program Corridor. Therefore, no 

impacts are anticipated at the Tier 1/Program EIS/EIR evaluation level under 

Build Alternative Option 1, 2, or 3.

Not applicable Not applicable

Would the Program result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the 

state?

Construction

Western Section – No Impact. No loss of availability of a known mineral 

resource would occur because no physical improvements are proposed or 

required within the Western Section. Therefore, no impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – Potentially Significant. Potential impacts on mineral 

resources and associated plans and policies under Build Alternative Option 

1, 2, or 3 are dependent on the location of rail infrastructure improvements

and station facilities, which are currently unknown. The Tier 2/Project-level 

analysis would identify and analyze impacts associated with the loss of 

availability of a known mineral resource.

LU-3 Potentially Significant. LU-3 would minimize, 

reduce, or avoid potential impacts from conflicts with 

plans and policies through design and further analysis. 

However, impacts may remain significant and 

unavoidable, as further analysis may determine that 

there is a conflict that cannot be mitigated between 

land uses.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in the loss of availability of a known mineral 

resource within the Western Section of the Program Corridor. Therefore, no 

impacts are anticipated at the Tier 1/Program EIS/EIR evaluation level under 

Build Alternative Option 1, 2, or 3.

Not applicable Not applicable

Eastern Section – No Impact. Once construction is complete, operation of 

Build Alternative Option 1, 2, or 3 would not result in the loss of availability of 

a known mineral resource within the Eastern Section of the Program 

Corridor. Therefore, no impacts are anticipated at the Tier 1/Program 

EIS/EIR evaluation level under Build Alternative Option 1, 2, or 3.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Would the Program result in the loss of availability of a locally important mineral resource recovery site delineated on a local general plan, 

specific plan, or other land use plan?

Construction

Western Section – No Impact. No loss of availability of a known mineral 

resource would occur because no physical improvements are proposed or 

required within the Western Section. Therefore, no impacts are anticipated at 

the Tier 1/Program EIS/EIR evaluation level under Build Alternative Option 1, 

2, or 3.

Not applicable Not applicable

Eastern Section – Potentially Significant. Potential impacts on mineral 

resources and associated plans and policies under Build Alternative Option 

1, 2, or 3 are dependent on the location of rail infrastructure improvements 

and station facilities, which are currently unknown. The Tier 2/Project-level 

analysis would identify and analyze impacts associated with the loss of 

availability of a locally important mineral resource recovery site.

LU-3 Potentially Significant. LU-3 would minimize, 

reduce, or avoid potential impacts from conflicts with 

plans and policies through design and further analysis. 

However, impacts may remain significant and 

unavoidable, as further analysis may determine that 

there is a conflict that cannot be mitigated between 

land uses.

Operation

Western Section – No Impact. The increase in train service (two additional 

round-trip daily trains within the Program Corridor) would not change existing 

land use and would not result in conflicts with locally important mineral 

resource recovery sites within the Western Section of the Program Corridor. 

Therefore, no impacts under Build Alternative Option 1, 2, or 3 are 

anticipated at the Tier 1/Program EIS/EIR evaluation level.

Not applicable Not applicable
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Impact Summary Mitigation Strategy Significance with Mitigation Strategy

Eastern Section – No Impact. Once construction is complete, operation of 

Build Alternative Option 1, 2, or 3 would not conflict with locally important 

mineral resource recovery sites within the Eastern Section of the Program 

Corridor. Therefore, no impacts under Build Alternative Option 1, 2, or 3 are 

anticipated at the Tier 1/Program EIS/EIR evaluation level.

Not applicable Not applicable

Notes:

AP=Alquist-Priolo; BMP=best management practice; EIR=environmental impact report; EIS=environmental impact statement; UBC=Uniform Building Code 
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3.10.8 Avoidance, Minimization, and Mitigation Strategies

Identified below are proposed programmatic mitigation strategies for further consideration in the Tier 

2/Project-level analysis. Specific mitigation measures, to the extent required, would be identified and 

discussed during the Tier 2/Project-level analysis after design details are known and specific impacts 

are identified. Potential mitigation measures would be developed in consultation with the agency with 

jurisdiction over the resource. 

Examples of programmatic mitigation strategies for geology, soils, seismicity, and mineral resources 

would include preparation of a preliminary geotechnical report to identify existing conditions, design 

considerations for alternative construction methods, and slope/soil stabilization measures where 

moderate to high effects are expected. Examples of programmatic mitigation strategies for 

paleontological resources would depend on the presence of significant paleontological resources 

and rock units with a high or undermined potential for containing significant fossils. Proposed 

programmatic mitigation strategies, consistent with state and federal regulations, include, but are not 

limited to, the following:

Mitigation Strategy GEO-1: During the Tier 2/Project-level analysis, a preliminary geotechnical 

report shall be prepared by a licensed geotechnical or civil engineer for the specific rail infrastructure 

or station facility proposed. The preliminary geotechnical report shall include, but not be limited to, 

analysis and recommendations on the following topics:

• Site preparation

• Soil-bearing capacity

• Appropriate sources and types of fill

• Liquefaction

• Lateral spreading

• Corrosive soils

• Structural foundations

• Grading practices

The recommendations identified in the preliminary geotechnical report shall be refined in a final 

geotechnical report. 
Coachella Valley-San Gorgonio Pass Rail Corridor Service Program – Draft EIS/EIR

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Mitigation Strategy PAL-1: During the Tier 2/Project-level analysis, the lead agency or agencies 

shall determine if a paleontological resources assessment report is required for the specific rail 

infrastructure or station facility proposed. If required, a paleontological resources assessment report 

shall be prepared for the specific rail infrastructure or station facility proposed. The report shall 

include, but not be limited to, analysis and recommendations on the following topics:

• Geologic context of the region and site and the potential to contain paleontological resources

• A records search of institutions holding paleontological collections from the Southern 

California region

• A review of published and unpublished literature for past paleontological finds in the area

If the paleontological resources assessment report identifies that paleontological resources are 

present at the site or if the geologic units to be encountered by the Project are designated as having 

a high paleontological sensitivity by the applicable local jurisdiction and lead agency, a 

paleontological resources impact mitigation program shall be prepared and implemented by a 

professional paleontologist as defined under Secretary of the Department of the Interior Standards. 

The paleontological resource impact mitigation program shall include, but not be limited to, the 

following: 

• The qualifications of the principal investigator and monitoring personnel

• Construction crew awareness training content, procedures, and requirements

• Measures to prevent potential looting, vandalism, or erosion impacts

• Location, frequency, and schedule for on-site monitoring activities

• Criteria for identifying and evaluating potential fossil specimens or localities

• A plan for the use of protective barriers and signs or implementation of other physical or 

administrative protection measures

• Collection and salvage procedures

• Identification of an institution or museum willing and able to accept any fossils discovered

• Compliance monitoring and reporting procedures
Coachella Valley-San Gorgonio Pass Rail Corridor Service Program – Draft EIS/EIR

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Mitigation Strategy HWQ-2: Based on the results of the Tier 2/Project-level analysis and 

recommendations, the construction of specific rail infrastructure or station facility proposed shall

comply with the provisions of the National Pollutant Discharge Elimination System General Permit 

for Stormwater Discharges Associated with Construction and Land Disturbance Activities (Order 

Number 2009-0009-DWQ, National Pollutant Discharge Elimination System Number CAS000002), 

and any subsequent amendments (Order Number 2010-0014-DWQ and Order Number

2012-0006-DWQ). These provisions shall include, but are not limited to, the following: 

• Construction activities shall not commence until a waste discharger identification number is 

received from the State Water Resources Control Board Stormwater Multiple Application and 

Report Tracking System. 

• Identification of good housekeeping, erosion control, and sediment control best management 

practices shall be utilized during construction activities. 

• A stormwater pollution prevention plan shall be prepared.

• A rain event action plan shall be prepared.

• A notice of termination shall be submitted to the State Water Resources Control Board within 

90 days of completion of construction and stabilization of the site.

These requirements, and any additional approvals, shall be determined in coordination with the 

governing agencies or local jurisdiction before construction on a project commences.

Mitigation Strategy LU-3: During a subsequent Tier 2/Project-level analysis, a land use consistency 

analysis shall be conducted by the identified lead agency or agencies to determine consistency of 

the Tier 2/Project-level improvement being proposed with the applicable local jurisdictional general 

plans or programs. If the land use consistency analysis identifies sensitive land uses or 

environmental resources within the Tier 2/Project-level Study Area, design or siting strategies shall 

be identified by the lead agency or agencies to avoid or minimize conflicts with sensitive land uses or 

environmental resources. 
Coachella Valley-San Gorgonio Pass Rail Corridor Service Program – Draft EIS/EIR

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